It is generally known for a film cassette to comprise a pair of housing parts, and a flexibly movable latching hook located on one of the housing parts and a rigid latching catch located on the other housing part which can engage to secure the two housing parts together. See, for example, prior art U.S. Pat. No. 4,294,418, issued Oct. 30, 1981, U.S. Pat. No. 4,160,605, issued Jul. 10, 1979, U.S. Pat. No. 3,648,952, issued Mar. 4, 1972, and U.S. Pat. No. 3,617,013, Nov. 2, 1971.
A problem occurring with the latching hook and the latching catch in the film cassette is that when the film cassette is subjected a mechanical shock due to its being dropped onto a hard surface, for example, the latching hook might move out of engagement with the latching catch. Prior art U.S. Pat. No. 3,648,952 suggests as a solution preventing the latching hook from assuming a completely unflexed position when it engages the latching catch. Thus, the biased condition of the latching hook might maintain it in engagement with the latching catch even though a mechanical shock is applied to the film cassette.